Green ebay laser help.

[c0rruptz]

Okay well, I bought a green 5mW laser pointer off ebay for about £10 the other day, just for fun. I planned on just messing around with it, you know. It worked amazingly for the first day, it's really good considering it's from ebay - you can see the beam outside at night easily. But today I charged up the AAA batteries and put them back in the laser, and it went all weird..

Basically there's like.. 3 stages of how bright it is.
The weakest is just like a 1mW standard laser or one of those cat toys you can get, really weak and it hardly reaches the houses across my street.

The second level is a little stronger, it's quite bright but it doesn't light the room up or anything.

The third level is the strongest, you can see the beam quite clearly outside in the dark and a kind of inside too. It pretty much lights the room up green too.

So yeah, when I press the button on the laser, its at the third level for about half a second then it goes to the second level... then after a while it goes to the first. I've tried charging the batteries up.. but its just the same thing happens.

Is this a problem with the laser itself, or what? Sorry if I rambled on I just like to be descriptive ><

It's one of these lasers btw.

 

[AndyR]

Should be normal considering it is from Ebay. Being a laser of lower quality, the power first has a "peak" of around the advertised mW, then slowly dies down to "cat toy" brightness.

I doubt there is anything you can do to fix it, next time buy one from a more trusted seller. It can still be cheap, but lasers from places like O-like or Rayfoss will still have stable power and good quality.

 

[x90z75ek]

Maybe it's because of the temperature.
Green lasers are more temperature sensitive than red or violet so when it's too cold the light dims.
Try warming it up and then turn it on, if it's still the same than it's what AndyR said.

 

[daguin]

With the speed at which it is changing, it appears to be mod hopping. Temperature could do that, but you can figure that out pretty easily by warming it against your body or setting it in a cool environment for awhile.

Shine the laser through a magnifying glass of some sort to defocus (make it biger and fuzzy) the beam and shine it on the wall near you. What is the 'shape" of the beam? Does the shape change as it gets dimmer? Does the beam "split" or get "hollow"?

Peace,
dave

 

[x90z75ek]

With the speed at which it is changing, it appears to be mod hopping. Temperature could do that, but you can figure that out pretty easily by warming it against your body or setting it in a cool environment for awhile.

Shine the laser through a magnifying glass of some sort to defocus (make it biger and fuzzy) the beam and shine it on the wall near you. What is the 'shape" of the beam? Does the shape change as it gets dimmer? Does the beam "split" or get "hollow"?

Peace,
dave

I've read about lasers mod hopping before on this forum several times now, but I never understood what it means. Could you explain what mod hopping means?

 

[3zuli]

^^basically it means changing the beam's profile
Transverse mode - Wikipedia, the free encyclopedia

 

[Deleted member 8382]

Try with alkaline batteries. If they don't solve it, your laser is broken. Buy this one:

https://www.dealextreme.com/details.dx/sku.1371

 

[BShanahan14rulz]

some greens are more finiky than others. Try better alkalines (1.65V fresh) as opposed to 1.2V rechargables.

If that doesn't work, get a new laser, then try a li-ion on the old one if you have some li-ions. If you don't have any Li-Ions, don't get them, they can be dangerous unless you know what you are doing.